I never was...
"I never was, am always to be,
No one ever saw me, nor ever will
And yet I am the confidence of all
To live and breathe on this terrestrial ball."
Hint: It never comes
No one ever saw me, nor ever will
And yet I am the confidence of all
To live and breathe on this terrestrial ball."
Hint: It never comes
Tomorrow
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(Source: http://www.telacommunications.com/misc/riddles.htm)